Solenoid locked push door



1946. w. HAMILTON SOLENOID LOCKED PUSH DOOR 2 Sheets-Sheet l INVENTOR WALLACE HAMlLTON BY t V ATTOiNEYS Filed Oct. 19, 1945 \.N k Q l ll :lllllllzlllli Nov. 19, 1946. w. HAMILTON SOLENOID LOCKED PUSH DOOR Filed Oct. 19, 1945 2 Sheets-Sheet 2 INVENTOR WALLACE HAMILTON ATTO EYS Patented Nov. 19, 1946 V 2,4ll,266

SOLENOID, LOCKED PUSH noon Wallace Hamilton, Albany, N. Y., assignor to 1 Consolidated Car-Heating Company, Albany, N. Y., a corporation of New York Application October 19, 1945, Serial No. 623,196

9 Claims.

This invention relates to improvements in door operating mechanisms and locking devices therefor.

The general object of this invention is to provide an improved and simplified mechanism for efiecting the opening and closing of doors particularly of the push type as frequently employed on vehicles of various types as, for example, buses.

An object of this invention is to provide a simple locking mechanism for this type of door in the form of a solenoid.

A more specific object of the invention is to provide a combination in which the solenoid lock acts to lock the door in the closed position, and also, if "desired, in the open position.

Another object is to provide a control in the combination of the foregoing object whereby the unlocking of the door for opening or closing is under the control of an attendant as, for example, the bus driver.

A broader object of the invention is to provide a push door operating and locking mechanism which may be applied to the rear or remote door or doors of a vehicle without causing undue accident hazards.

Still another object of the invention is to provide a push door construction. which permits of opening the door by pushing thereon and wherein there is employed a spring operated motor, such as a door check, for closing the door.

Other andmore detailed objects of the invention will be apparent'from the following description of the single embodiment thereof illustrated in the attached drawings.

This invention resides substantially in the combination, construction arrangement and relative location of parts as will be described in detail below.

In the accompanying drawings- Figure l is an elevational View of the mechanism of this invention and a portion of the doors over which it is mounted when viewed, in the case of application to a vehicle, from the inside thereof;

Figure 2 is a top plan view of the mechanism of Figure 1 showing some parts in cross-section and some parts broken away to improve the illustration, the parts being shown in door closed position;

Figure 3 is a view similar to Figure 2 showing the doors in full open position;

Figure 4is a, diagrammatic and schematic circuit arrangement for controlling the solenoid look so as to lock the door in both open and clos d position; and

2 Figure 5 is a diagrammatic and schematic circuit arrangement for controlling the solenoid lock so as to lock the door in closed position only. The description of the mechanism and its operation will be given under the assumption that the invention has been applied to a vehicle such as a modern motor coach, although it will be apparent from the disclosure that the invention is not limited to such use and indeed is not limited to use on vehicles. assumption and as is quite frequent practice, a pair of door shafts H3 and II are iournaled in suitable bearing members on vertical parallel axes at the side edges of the door opening. 1 In the form o-fmechanism illustrated, the door com prises a pairof leaves 12- and I3 attached to the shafts m and I l, respectively, for rotation therewith and meeting on a vertical central line with respect to the door opening; As will appear later, these door leaves swing froma common plane when in closed position outwardly and away from each other to a position at right angles to the door closed plane so as to project exteriorly of the vehicle. The shafts I0 and H are shown journaled on their upper ends in any suitable form of bearing members l4 and I5 mounted on some suitable portion of the bus structure. Ex tending across the top of the door opening and lying in a horizontal plane is a lintel or other suitable form of supporting plate I6 on which the overhead mechanism is mounted. In this casethis mechanism includes a suitable form of supporting L-shaped bracket 2! on which the mechanism parts are mounted.

Attached to the door shafts l0 and II for rotation therewith are the levers l1 and I8 which are respectively connected'by means of rigid links or rods l9 and 20 to the arms 21 and 29 of a threearmed lever which includes the arm 28. The arm 28 is pivotally connected by the link 26 to a bell crank lever having the arms 24 and 25 pivotally mounted on the pin 23 forming part of a standard 22 mounted on the bracket 2|.

The three-pronged lever is secured to the rotat'alble shaft of any suitable form of commonly used spring biased type of door check 3| which is shown secured to the vertical wall of In accordance with this,

solenoid is connected to the movable contact of a single pole double throw switch 40 adapted to be placed under the control of an attendant as, for example, the bus operator. In this figure the single-pole double-throw switch 33 is diagram matically illustrated and is shown with its movable contact connected to the other terminal of the current source 39 The fixed contacts of the switches 33 and 40 are connected together in pairs as shown.

The following comprises a description of the operation of this mechanism. The circuit of Figure 4 shows the position of the switches when the door is closed and locked at which time the solenoid 37 is energized as follows: Current flows from the source 39'through the winding of the solenoid 31 to the movable contact of switch 4|], from there to the movable contact of switch 33 and back to the current source 39. Thus the solenoid 31 is energized.

V Figure 2 shows the linkage system of the doors in the position they assume when the door is closed at which time the'inner end of the plunger 36 is closely adjacent to the fixed core 38 of the solenoid. I In'order to condition the door so that it may be pushed open the vehicle operator at the proper time operates switch 40 from the position shown in Figure 4 to its other position breaking the circuit to the solenoid 31 in an obvious mannen A person wishing to alight through the doors pushes on one or both leaves thereof causing a reaction through the linkage system to elfect clockwise rotation (Figure 2) of the three-armed lever 212B29 from the position shown in Fi ure 2 to the ultimate position shown in Figure 3. The first movement of the three-armed lever causes clockwise rotation of the bell crank 25-24 which it will be seen causes the plunger 36 to move to the right, that is away from the core 38. From the kinematics of the linkage system it will be apparent that as rotation of the three-armed lever continues, the bell crank will reach a position of rest at the end of its clockwise rotation and then as the three-armed lever continues to rotate in a clockwise'rotation, as the doors approach full open position, the bell crank'lever will begin'to rotate-in a counterclockwise directiOIlr'fThiS movementof the bell crank will continue with the parts properly proportioned so that when the door is fully opened plunger 36'will move back to its initial position most closely adjacent, with respect to its end,,to the fixed core 38.

When the door'begins to open the lower portion cam 32 will operate the switch 33' to disconnect the current source from the upper contact (Figure 4) and hold that position until the door reaches fully open position, at which time the higher portion of cam 32 will move the switch arm stilljfurther (see Figure 3), at which time the switch will close on the lower contact completing a circuit from the left hand contact of switch 40 through switch 33 for the solenoid 31 which becomes energized and locks the door in open position. During the'opening movement the spring of the door check 3| is beingstIfeEiS d K? minimum force.

a point of maximum stress when the door is fully open. It, of course, tends to close the door but the solenoid prevents this. After all the passengers have moved through the doorway the vehicle operator moves switch 40 back to its original position de-energizing the solenoid 31 in an obvious manner. This releases the door so that the stress spring in the door check; can return all of the parts including the door leaves to closed position. The operation of switch 33 is reversed so that just as the door is fully closed solenoid 31- is again energized to lock the door in closed position. It will, of course, be understood by those skilled in the art that switch 40 can be tied in in many ways with the operation of the vehicle so that its operation is automatic.

In conditions of use where it is not necessary to lock the door open a very simplified circuit arrangement as shown in Figure 5 can be employed, in which case the manual switch 40 is merely opened when it is desired to free the doors for opening, and remains open until the door is closed, whereupon it is closed to re-energize the locking magnet. Of course, in this case the switch 33 and the cam operator 32 are not employed.

A study of the linkage system will show that when the door is closed and although the toggle arrangement formed by the links i9 and 20 and the three-armed lever is not in straight line arrangement it is nearly so, with the result that a relatively small force exerted by the solenoid, 31 when its effect is multiplied through the bell crank connection, in effect exerts a much greater force to prevent the opening of the doors. It will be noted that the plunger 36 is closely adjacent to the core during door open and door closed position so that the maximum eiiect of the magnetic field is secured. Similarly, when the door is locked in open position the bell crank and connecting links with the three-armed lever magnify the force exerted by the magnet so that a large force would have to be applied to the doors to close them.

A very important and practical feature of this invention resides in the fact that the toggle linkage system is so arranged and the plunger 3t'is so positioned with respect to the core 38 that a maximum closing eiiortis applied to the door just before it reaches fully closed position. It will be understood, upon consideration, that at that time the door check spring is exerting its minimum closing eiiect-since it is most nearly relaxed. Thus the locking magnet and linkage system are contributing their maximum closing elTect at the time when most needed, namely when the door check is least active for that-purpose.

A further feature of this arrangement resides in the fact that again the maximum magnet and linkage actions are exerted when the door is closed, thereby resisting any tendency of the doors under the centrifugal forces incident to operation of the vehicle from tending to open even slightly. Of course, it is at this very time that the spring of the door check is exerting its rangement of the locking magnet parts and linkage system as disclosed, any tendency of the door to open at an undesired time is com letely prevented. i

From the above description it will be apparent to those skilled in the art that the structural. details of this invention are capable of consider a l ia i n Without departure from the novel Thus, by the interactin are subject matter herein disclosed. I do not, therefore, desire to be limited by the disclosure which has been given in an illustrative sense but rather by the terms of the appended claims.

What is claimed is:

1. In a door operating system, the combination including a pair of door shafts, a spring biased door check having a multiple armed lever connected thereto, linkage systems for connecting said shafts to a pair of the arms of said lever, a solenoid having a reciprocable plunger, and a linkage system interconnecting said plunger with another arm of said lever, said plunger lying in the same position with respect to said solenoid for door open and door closed positions.

2. In a door operating system, the combination including a pair of door shafts, a spring biased door check having a multiple armed lever connected thereto, linkage systems for connecting said shafts to a pair of the arms of said lever, a solenoid having a reciprocable plunger, and a linkage system interconnecting said plunger with an arm of said lever and adapted to cause the plunger to move from an initial position and back to that initial position during the opening or closing movement of the door shafts.

3. In the combination of claim 1, means for energizing said magnet including a switch operated upon movement of said door shafts to interrupt the circuit of said solenoid at the beginning of opening movement and to complete it at the end of the opening movement.

4. In the combination of claim 2, means for energizing said magnet including a switch operated upon movement of said door shafts to first de-energize said solenoid at the beginning of opening movement and to energize it again at the end of the opening movement.

5. In the combination of claim 1, circuit means for energizing said solenoid including a switch operated by said door check for controlling the energization of said solenoid.

6. In the combination of claim. 1, circuit means for energizing said solenoid including a manual switch and a switch operated by said door check whereby when the manual switch is positioned for door opening operation the other switch reenergizes the solenoid at the end of the opening and closing movements.

7. In the combination of claim 1, circuit means for energizing said solenoid including a switch for energizing the solenoid to lock the door in closed position.

8. In a door operating system, the combination including a door shaft, a spring biased door check, a toggle linkage system for connecting said shaft and door check, a solenoid having a reciprocable plunger connected to said linkage system, and means for controlling the energization of said solenoid, said magnet and toggle linkage system exerting a maximum closing effort on. said shaft When it is in door closed position.

9. In the combination of claim 8, the spring of said door check being most relaxed in door closed position of said shaft and said solenoid and magnet system at that time exerting a maximum closing effort.

WALLACE HAMILTON. 

